Out barking at the moon again

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Tonight I had another attempt, first clear skies and cold weather in a while that also had a moon up. Again with the D5, the 500 PF and the TC14.

This is a stack of 40+ images that I just applied lens corrections to, then sent to PS for noise reduction using a stack with median filter used to reduce noise. I still need Nikon to make me a D860 or Z9, but while waiting that one out I'll spend more time (re)learning LR/PS-skills I have lost over the years.

Improvements from last time is that I now have a proper shoe for the lens to get it on the tripod solidly.

moon-191108-1.png
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This is probably breaking all kinds of rules for spamming, but I had a go again tonight, and used a tool called Sequator to help deal with noise. Alignment and cropping was done in PS.
It might just be a hefty dose of confirmtion bias, or a firm belief in DOnning-Kruger, but this looks marginally better?

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-A
 
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Tonight I had another attempt, first clear skies and cold weather in a while that also had a moon up. Again with the D5, the 500 PF and the TC14.

This is a stack of 40+ images that I just applied lens corrections to, then sent to PS for noise reduction using a stack with median filter used to reduce noise. I still need Nikon to make me a D860 or Z9, but while waiting that one out I'll spend more time (re)learning LR/PS-skills I have lost over the years.

Improvements from last time is that I now have a proper shoe for the lens to get it on the tripod solidly.

View attachment 1649575
They both look good, but why stack so many images?
 
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Good question. Call me back in a year and I just might have an answer. I'm just getting into taking pictures with the lens pointed up, and clearly there is a lot more techniques and processing involved in this domain than what my previous landscaping has needed. I'm just trying to nail down a workflow and learn how the various components of the flow affect the final results and how it all works out. :)
Also, I'm coming more to terms with my whinging about pixles helps me driving more into how the tools work, so that leaves me with more to learn.
 
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I think I figured out my biggest mistake. Don't do lens corrections in LR before sending it off to PS to align and crop. Looks like Sequator has a lot easier time dealing with noise and producing something that can be reasonable sharp after merging. I think this version came out better. Now off to bed.
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Not stacking to combine different exposures (moon and stars), but stacking to remove noise. The last image is a lot cleaner than any single image out of the camera. If I sharpen a single frame from the camera then it brings out heaps of noise, then I stack to reduce noise it seems to be a better base to sharpen from.
The only part I don't understand is why the Copernicus carater is completely blotched out on the original frames from the camera; there's lots of other parts that are sharp-ish.
 
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Alexander, I definitely see the improvement in the third image. Just to make sure I understand your workflow: did you bring the raw files into PS for alignment, then Sequator to stack, then returned LR for final processing?
 
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Alexander, I definitely see the improvement in the third image. Just to make sure I understand your workflow: did you bring the raw files into PS for alignment, then Sequator to stack, then returned LR for final processing?
Yes, that is what is done for the last one and became my final iteration for the process. Also when aligning in PS I always used "reposition" and never asked it to change the images, that turnes out to give the best result.

-A
 
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Thanks for the input. I think it's showing improvement, and I've been trying to structure all the inputs I have in how to approach this. Here's a collection of what is in my notes so far:

- Get as low ISO as you can, with the moon that is no issue even with 800mm; it's basically a very brightly lit object. I've yet to see how this pans out with less than half a moon.
- If you are doing stacking for any reason, do not apply *any* corrections when importing the input pictures for the stack, as this may interfere with alignment of pixles. Do lens corrections and other tuning after whatever stacking and merging is done, if needed.
- "Stacking" is a non-specific term. Stacking is used for multiple different ways of enhancing the final picture. Here's the different ways I've figured stacking plays out:
- Stacking to combine motives of very differing light intensity (i.e. moon and stars, milkey way and landscape foreground, I've even used it in daylight to get indoor shots with exposures out through windows good on sunny days.). This basically requires one solid image of each layer, and each of these images may be stacks in their own right (see next items).
- Stacking to reduce random input noise. This basically improves with more exposures to draw from, and software such as Sequator or PS' "median filter" are tools to accomplish this. This is the big change between the last and second to last image above here. This requires multiple exposures, it seems to be roughly logarithmic in number of exposures (i.e. of 100 exposures, the biggest gain in result happens in the first 10-15 exposures). Sequator seems to be a *lot* faster than PS in combining exposures to a final result in this method.
- Stacking to reduce random noise in the camera chip itself, also called "dithering" by astrophotographers. This works to remove as much of the noise introduced by the chip capturing the image. This works by slightly moving the camera/lens so that the image is shifted on the chip between exposures. Tracking a moon at 500+ mm achieves this automagically as it's a fast moving target.
- Stacking black frames. this helps identify hot pixels and also any capture issues intrinsic to the camera system (i.e. red/purple banding on very low light captures, e.g. milky way shots or lower brightness).

Then once you have your output from the stacking, go ahead and do lens corrections, tinker with exposure and colour, details and sharpening, etc.

Thats it thus far. :)

-A
 
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